source: http://www.securityfocus.com/bid/2167/info

Windows Media Player is an application used for digital audio, and video content viewing. It can be embedded in webpages as an ActiveX control.

It is possible to execute a javascript URL from within the Windows Media Player ActiveX control embedded in HTML. This javascript can be executed in arbitrary "already open" frames, specified within the ActiveX control. By doing this, an attacker can take over the frame's DOM (document object model), bypassing security restrictions. This would be accomplished through a special webpage and having the victim visit the webpage.

An attacker exploiting this vulnerability can read files on the users filesystem and reportedly execute arbitrary programs on the victim host. 

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Windows Media Player 7 and IE vulnerability - executing arbitrary programs
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Windows Media Player 7 and IE vulnerability - executing arbitrary programs
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alert("This page reads C:\\test.txt");
window.open("file://c:/test.txt","georgi");
function f()
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document.o1.object.launchURL("javascript:alert(document.body.innerText)");
}
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